Air con broken..

Put a set of gauges on an see if any gas is still in there, if yes ck. ele. switch next.

 

pull cover off heater box, find temp con. switch 2 wires CK. for power,cross them, listen for click of a/c clutch kicking on or use test light to CK. for power at clutch, on HI. side AC. line look for cut off switch, ck. for 12 v, an cross em, low side may have one also do same, what year is this one?

 

If he walked it's electrical. Have you checked the relay? Pin 30 is B+ and pin 85 should have 12V with the AC switch and fan on.

The best way to check that low pressure switch is with an ohmmeter. If there is pressure the switch is closed and no resistance. If you use a jumper on the switch the compressor should come on. If it doesn't then most likely it's the relay or the freeze switch on the high pressure side.

Power goes from the inside switch to the relay to the freeze switch then to the low pressure switch then to the compressor. I never worked on a Volvo but most systems are similar.

 

Not being smart, but did you make sure the AC switch on the dash is on? These friggin' Volvos are backwards for that switch, if the light is on the AC is off.

 

you need to recover the system and make sure its full , if it 1 lb low it will not come on , what year and make of volvo is it ? the newer one have a pressure switch just right of the air cleaner housing , its the only pressure swtich , on the older one there is two of them , on the older ones there is a apads system over by the dirver side that should be blinking a slow green light ,if not you will need to take to a volvo shop and have freon recovered and have the system tested .